Dear MiloL:
I respectfully have to disagree with you. You stated that "if you learn language A from birth and learn B later you will always think in language A" I speak four languages and never do that. I think in the language I am using at the moment. That only happens when one doesn't master the language but once master the language that is no longer needed, it is possible to think in any other language.
I am persuaded that thought is always there and language is only the way we express it.